Frying onions is a must. Besides that it depends with what you serve it, most Italians use passata as tomato sauce, add some salt and pepper, maybe basiloco or garlic. Adding small pieces of carrots is an option aswel, although personally I never do this. Then leave it on low fire for ~20 minutes.
Italian cooking techniques are quite easy tbh. My dad used to say that garlic belongs with fish and onions with meat, but I think it really differences per family or region. Most regions in Italy have their own traditional ways.